Hi Folkes,, I see many references re; Ex135's malfunctioning Hydraulics= Boom / Dipper etc not working, So think it is relatively common fault. I have similar , my machine will not lower Boom, Was functioning OK , E51 showing on front screen but I am not sure if that is relevant (or working ) This excavator is new to me. I have checked electrical connections, tried reversing pilot control on the spool valve I believe may be dipper Am in remote area of Thailand, Can any one throw me some clues?
Ex135 Not computor savvy ,,,typo mistake re switching Pilot control to dipper/ obviously I meant Boom. Can anyone advise me which spool bank functions the BOOM? Cheers Greg
Still Knackered on this, Have now followed Boom piping to correct spool, piping id A3 leads to what I think is the third valve in from the outside. have checked and cleaned anything I can find in electrical connections for anything looking obvious, tried swapping pilot piping to the top of the valve's, getting reverse operations of tracks etc. But when I switched pilot control on the tops of valve 3 or four, still could not power boom down.
The boom spools( there is 2 in the control valve) are the 3rd spools back from the travel spools. Its difficult to explain because the control valve sits sidewards on this machine as opposed to front to rear. When you try and lower the boom does the engine load up as though the pumps are going under load? Is the boom cylinders fitted with hose rupture valves? The only thing i can think of without more info is the boom anti drift valve. Basically when you lower the boom, pilot pressure pushes on the boom spool to lower. I'm sure only 1 spool is opened to lower the boom. The pilot pressure also pushes on the boom anti drift selector valve which in turn activates the anti drift valve and lets the oil from the boom cylinder back to the tank. This could be jammed and not opening. This valve is located in line with both boom spools. I think its square in shape, held on with 4 bolts. Try stripping that and checking it.
Thanks very, very much for your responce Gary, I had correctly id'd 1 boom spool valve , but hadn't twigged there was 2 I am pretty sure that the cylinder's don't have anti rupture valves No the engine doesn't load up or labour under pressure, when I try to lower the boom. Cheers and thanks again, it is deeply appreciated
Do you have a model code for the machine? It should be part of the serial number. I'm struggling to find the correct manuals for it. Is it definitely a EX135UR-5? I'd be looking to make sure you have a pilot feed to the spool. Follow the hose from the top side of the boom cylinders and see if it goes in the top or bottom of the control valve. Then put a gauge in the pilot line going to the control valve and see what your getting when you push the boom lever forward. You'll need to identify if its a main circuit or pilot circuit issue
I have Model/type EX135UR-5 Product ID #1EUPOO3299# Have LOcated what i think must be the Anti drift valve, it is branched in to the pilot control from the bottom of the spool valve and sits forward of the actual spool valves. Mind you, this Norfolk Dumpling doesn't know just what an "anti drift" is as drifting to me is sideways I am fairly sure that the "A3" Hydraulic hoses go to feed the top section of the spool vaLVE Cheers greg
Good Day Gary ,, thanks for your efforts to help, The Hitache dealership system here in Thailand, confuses me with only Bangkok showing Dealerships,, but I finally got through to a Local Dealer. the faults were in the control valves under the Operators cabin. Some of the Local Labour ain't crash hot, but anyone with a Blue Ford tractor or such, is likely to be an expert and just about everybody in the village seems to know more than any Farang (foreigner) However I was very pleased to get a couple of local Hitache Lads out that really knew their stuff. Thank you very much for your much appreciated information. Keep Well. Cheers Greg